Method and apparatus for stabilizing combustion system performance

ABSTRACT

A combustion system includes an ionizer configured to eject charges (or accept charges) for uptake by a combustion reaction to cause a combustion reaction to carry a majority charge or voltage. The ionizer includes an inner electrode, a dielectric body surrounding the inner electrode, and one or more conductive or semi-conductive inner electrodes disposed on the surface of the dielectric body. The inner and outer electrodes are configured to be in a capacitive relationship.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. Divisional Application of co-pendingU.S. patent application Ser. No. 15/090,483, entitled “IONIZER FOR ACOMBUSTION SYSTEM,” filed Apr. 4, 2016 (docket number 2651-195-03). U.S.patent application Ser. No. 15/090,483 is a U.S. Continuationapplication which claims priority benefit under 35 U.S.C. § 120(pre-AIA) of International Patent Application No. PCT/US2014/059358,entitled “IONIZER FOR A COMBUSTION SYSTEM,” filed Oct. 6, 2014 (docketnumber 2651-195-04), now expired. International Patent Application No.PCT/US2014/059358 claims priority benefit from U.S. Provisional PatentApplication No. 61/887,333, entitled “ION SOURCE FOR A COMBUSTIONSYSTEM,” filed Oct. 4, 2013 (docket number 2651-195-02), now expired.Each of the foregoing applications, to the extent not inconsistent withthe disclosure herein, is incorporated herein by reference.

BACKGROUND

Combustion systems typically include a fuel source and oxidant source.The fuel and oxidant are mixed together in a combustion chamber and acombustion reaction is initiated and sustained. The heat from thecombustion reaction can be used to generate electricity, to heatmaterials in industrial processes, to drive endothermic chemicalreactions, and many other applications. The characteristics of acombustion reaction determine how effectively these purposes can becarried out. It is desirable to be able to manipulate a combustionreaction in a selected manner to improve the effectiveness of thecombustion reaction.

SUMMARY

One embodiment is a combustion system including a fuel source and burnerfor initiating and maintaining a combustion reaction in a combustionvolume. An ionizer is positioned adjacent the combustion reaction,separated from the combustion reaction by a gap including a dielectricgas. The ionizer includes an inner electrode coupled to a high voltagepower source. The inner electrode is covered by a dielectric body. Anelectrode is positioned on an outer surface of the dielectric body andelectrically insulated from the inner electrode by the dielectric body.The electrode is nevertheless capacitively coupled to the innerelectrode. When the power source supplies a high voltage to the innerelectrode, a high voltage is similarly induced on the electrode via thecapacitive coupling. The high voltage on the electrode can be used tomanipulate a characteristic of the combustion reaction.

In one embodiment, the combustion system includes a counter electrodepositioned in or near the combustion reaction. The counter electrode iscoupled to the power supply and configured to receive a second voltagefrom the power supply. The second voltage is imparted to the combustionreaction by the counter electrode, which is electrically coupled to thecombustion reaction. In one embodiment, the second voltage is ground. Byapplying respective voltages to the counter electrode and the innerelectrode, the combustion reaction can be manipulated to obtain adesired effect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a combustion system including an ionizer to applyan electrical potential to a combustion reaction, according to anembodiment.

FIG. 2 is a diagram of a combustion system including an ionizer to applyan electrical potential to a combustion reaction, according to anotherembodiment.

FIG. 3 is a diagram of a combustion system including an ionizer to applyan electrical potential to a combustion reaction, according to anotherembodiment.

FIG. 4A is a cross sectional diagram of the ionizer of FIG. 1, accordingto one embodiment.

FIG. 4B is a cross sectional diagram of an ionizer, according to oneembodiment.

FIG. 5 is a cross sectional diagram of an ionizer, according to oneembodiment.

FIG. 6 is a diagram of a combustion system including an ionizer and anannular counter electrode, according to one embodiment.

FIG. 7 is a diagram of a combustion system, according to one embodiment.

FIG. 8 is a flow diagram of a process for operating a combustion system,according to one embodiment.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. Other embodiments may be used and/or other changesmay be made without departing from the spirit or scope of thedisclosure.

FIG. 1 is a diagram of a combustion system 100 including an ionizer 101to apply an electrical potential to a combustion reaction 110, accordingto an embodiment. As used herein, the term “ionizer” refers to anapparatus configured to generate charged particles, which can be ions(atoms including an atomic nucleus and missing or additionalelectron(s)) or electrons. The ionizer 101 for a combustion system 100includes an inner electrode 112 and a dielectric body 104 having aninside surface 106 and an outside surface 108. The dielectric body 104is configured to maintain high electrical resistance in the presence ofa combustion reaction 110. The inner electrode 112 is disposed insidethe dielectric body 104, the inner electrode 112 being electricallyinsulated from the combustion reaction 110. One or more outer electrodes114 are disposed outside the dielectric body 104 in capacitivecommunication through the dielectric body 104 with the inner electrode112. A high voltage power supply 116 has first and second voltage outputnodes 118, 122 operatively coupled to the inner electrode 112 and to aconductive combustion support structure 124, respectively.

The high voltage power supply 116 can apply a periodic voltage signal tothe inner electrode 112 via the first voltage output node 118. Theperiodic voltage signal can be selected to cause ejection of electricalcharges between the one or more outer electrodes 114 and a dielectricgap 120 disposed between the outer electrodes 114 and the combustionreaction 110. In some embodiments, the dielectric gap 120 includes a gasthat acts as a dielectric to prevent direct electrical continuitybetween the combustion reaction 110 and the outer electrodes 114. Insome embodiments, a source of cool gas can maintain a flow of cool gasin the dielectric gap 120. For example, the cool gas can includecombustion air. In some embodiments, the ejection of electrical chargescan be periodic and synchronous with the periodic voltage.

The periodic voltage signal can include a first portion characterized bya positive voltage. The outer electrodes 114 can receive electrons fromthe dielectric gap 120 during the positive voltage portion of theperiodic voltage signal, resulting in ejection of a positive chargedparticle. The periodic voltage signal can include a second portioncharacterized by a negative voltage. The outer electrode 114 can ejectelectrons into the dielectric gap 120 during the negative voltageportion of the periodic voltage signal.

The high voltage power supply 116 can be configured to output a periodicvoltage signal having a peak-to-peak difference of 40,000 volts or more.In some embodiments, the high voltage power supply 116 can be configuredto output a periodic voltage signal having a peak-to-peak difference of100,000 volts or more. Optionally, the high voltage power supply 116 canapply an asymmetric waveform including a first portion having onepolarity configured to eject charged particles of the same polarity, anda second portion of opposite polarity at a voltage insufficient to ejectcharged particles of the opposite polarity. Moreover, as will bedescribed below, the ionizer 101 can be structured to preferentiallyeject charged particles having a selected polarity (e.g., by doping theouter electrodes 114).

The periodic voltage signal can include an alternating current (AC)voltage waveform. Additionally or alternatively, the periodic voltagesignal can include a direct current (DC) chopped voltage waveform. TheDC chopped voltage waveform can be DC offset from voltage ground. The DCchopped voltage waveform can include a square or a sawtooth waveform,for example.

In one embodiment, the dielectric body 104 can include fused quartz.Alternatively, another suitable dielectric material can be used for thedielectric body 104.

In one embodiment, the conductive combustion support structure 124 is afuel nozzle configured to emit fuel and hold the combustion reaction110. Alternatively, the conductive combustion support structure 124 caninclude a flame holder disposed adjacent to or in a fuel jet andconfigured to hold the combustion reaction 110. The conductivecombustion support structure 124 can be disposed for at least periodicelectrical continuity with the combustion reaction 110 by which avoltage can be imparted to the combustion reaction 110 from the highvoltage power supply 116. The conductive combustion support structure124 can receive ground voltage, or another voltage signal, from the highvoltage power supply 116 via the second voltage output node 122.Additionally or alternatively, the conductive combustion supportstructure 124 can be electrically isolated from electrical ground.

In various embodiments, the inner electrode 112 can include a solidconductor, a metal mesh, a stranded structure, stainless steel, and/or asuperalloy such as Inconel.

The one or more outer electrodes 114 can be shaped to cause an electricfield curvature in the dielectric gap 120 disposed between the outerelectrode 114 and the combustion reaction 110. In some embodiments, theone or more outer electrodes 114 can be shaped to have a lateral extentless than about 0.10 inch. In some embodiments, the one or more outerelectrodes 114 can be shaped to have a lateral extent less than about0.02 inch in at least one dimension along the outside surface 108 of thedielectric body 104. The one or more outer electrodes 114 can include ametal, stainless steel, and/or Inconel.

FIG. 2 is a diagram of a combustion system 200 including an ionizer 201to apply an electrical potential to a combustion reaction 110, accordingto another embodiment. The one or more outer electrodes 114 can includea semiconductor. The semiconductor can include germanium, dopedgermanium, silicon and/or doped silicon.

The one or more outer electrodes 114 can include a p-dopedsemiconductor. The one or more p-doped semiconductor electrodes 114 canbe configured to receive electrons from the dielectric gap 120 adjacentto the inner electrode 112 during a time interval when the innerelectrode 112 is held at a positive voltage. Additionally oralternatively, the one or more p-doped semiconductor electrodes 114 canbe configured to minimize an ejection of electrons to the dielectric gap120 adjacent to the inner electrode 112 during a time interval when theinner electrode 112 is held at a negative voltage. Additionally oralternatively, the one or more p-doped semiconductor electrodes 114 canbe configured to eject positive charges to a dielectric gap adjacent tothe inner electrode 112 during a time interval when the inner electrode112 is held at a positive voltage.

The one or more outer electrodes 114 can include an n-dopedsemiconductor. The one or more n-doped semiconductor outer electrodes114 can be configured to eject electrons to the dielectric gap 120adjacent to the inner electrode 112 during a time interval when theinner electrode 112 is held at a negative voltage. Additionally oralternatively, the one or more n-doped semiconductor electrodes 114 canbe configured to minimize an ejection of positive charges to thedielectric gap 120 adjacent to the inner electrode 112 during a timeinterval when the inner electrode 112 is held at a positive voltage.

The one or more outer electrodes 114 can include both p-dopedsemiconductor outer electrodes 114 and n-doped semiconductor outerelectrodes 114. The one or more p-doped semiconductor outer electrodes114 can be configured to receive electrons from the dielectric gap 120adjacent to the inner electrode 112 during a time interval when theinner electrode 112 is held at a positive voltage. Additionally oralternatively, the one or more n-doped semiconductor outer electrodes114 can be configured to eject electrons into the dielectric gap 120adjacent to the inner electrode 112 during a time interval when theinner electrode 112 is held at a negative voltage. The p-doped andn-doped semiconductor outer electrodes 114 can be arranged in aninterleaved pattern on the outside surface 108 of the dielectric body104. In this embodiment, the n-doped semiconductor outer electrode(s)114 act(s) to increase electric field curvature around the p-dopedsemiconductor electrode(s) 114 during a time interval when the innerelectrode 112 can be held at a positive voltage. Additionally oralternatively, the p-doped semiconductor outer electrode(s) 114 act(s)to increase electric field curvature around the n-doped semiconductorelectrode(s) 114 during a time interval when the inner electrode 112 canbe held at a negative voltage.

The dielectric body 104 can include shapes other than tubular. Forexample, the inner electrode 112 can be configured as a planar element.The dielectric body 104 can be formed from a planar material such as twofused quartz sheets. The fused quartz sheets can be arranged superjacentand subjacent to the planar inner electrode 112 with some margin aroundthree or more edges of the inner electrode 112. A metal lead operativelycoupled to the inner electrode 112 can optionally be placed to emergefrom between a margin in the quartz sheets along a fourth edge of theinner electrode 112. The edges of the subjacent and the superjacentquartz sheets can be heated to fuse together, leaving an inner electrode112 that is insulated. In an embodiment, the outer electrodes 114 can bedisposed around one or more of the fused quartz edges. Placing the outerelectrodes 114 in this location can, for example, help to reduceelectric field shadowing of the electrodes 114 by the inner electrode112. Other shapes may be substituted for a planar and rectangular innerelectrode 112 and planar and rectangular quartz sheets.

FIG. 3 is a diagram of a combustion system 300 including an ionizer 301configured to apply an electrical potential to a combustion reaction110, according to an embodiment. The ionizer 301 is substantiallysimilar to the ionizer 101 of FIG. 1 except that the outer electrodes314 of FIG. 3 have a circular cross section.

In one embodiment the outer electrodes 314 are individual electrodesphysically separated from each other. Alternatively, the outerelectrodes 314 can all be a same thin wire wound around the ionizer 301.

FIG. 4A is a cross section of the ionizer 101 of FIG. 1, according toone embodiment. The ionizer 101 includes a cylindrical inner electrode112. The cylindrical inner electrode 112 is covered by a layer of thedielectric body 104. The inside surface 106 of the dielectric body 104is in contact with the inner electrode 112. The outer electrode 114 ispositioned on the outside surface 108 of the dielectric body 104.

In the embodiment of FIG. 4A, the outer electrode 114 is a sharpelectrode. The outer electrode 114 is electrically insulated from theinner electrode 112 by the dielectric body 104 such that an electricalcurrent will not flow between the outer electrode 114 and the innerelectrode 112. However, the outer electrode 114 is capacitively coupledto the inner electrode 112 via the dielectric body 104 separating theinner electrode 112 from the outer electrode 114. Due to the capacitivecoupling between the inner electrode 112 and the outer electrode 114,when a voltage is applied to the inner electrode 112, the voltage on theouter electrode 114 will also change. By applying a high voltage to theinner electrode 112, a high voltage can be induced on the outerelectrode 114.

When a second voltage (for example, ground voltage) is applied to astructure near the combustion reaction 110, such as the conductivecombustion support structure 124, a high charge density will accumulateat the outer edges of the outer electrode 114 and particularly at theouter corners of the outer electrode 114. The high charge density cancorrespond to a particularly high density of electrons or the absence ofelectrons at the outer edges of the outer electrode 114 depending on thepolarities of the voltages on the inner electrode 112 and the conductivecombustion support structure 124. For example, if the high voltage onthe outer electrode 114 has a negative polarity with respect to thecombustion reaction 110, then a high density of electrons willaccumulate at the outer edges of the outer electrode 114. If the highvoltage on the outer electrode 114 has a positive polarity with respectto the combustion reaction 110, then electrons will flee the outer edgesof the outer electrode 114 resulting in a high density of positivecharges at the outer edges of the outer electrode 114.

The high charge density at the outer edges of the outer electrode 114results in a very strong electric field near the outer edges of theouter electrode 114. The strong electric field near the outer electrode114 can affect the combustion reaction 110 in various ways. The outerelectrode 114 can eject charge into the combustion reaction 110 or thedielectric gap 120. The outer electrode 114 can also induce ionizationof gases in the dielectric gap 120. Additionally, the electric fieldfrom the outer electrode 114 can influence the combustion reaction 110without ejecting charges or ionizing material in the dielectric gap 120.By selecting the respective voltage polarities, respective voltagemagnitudes, the width of the dielectric gap 120, and, in the case wheremultiple outer electrodes 114 are present, the relative positioning ofthe outer electrodes 114, the characteristics of the combustion reaction110 can be manipulated in a desired manner. For example, the combustionreaction 110 can be manipulated to more thoroughly combust the fuel, toreduce pollutants, to stretch the length of the combustion reaction 110,to contract the length of the combustion reaction 110, to change color,to make the combustion reaction 110 not apparent, etc.

In one embodiment, the outer electrode 114 can be electrically connectedto the high voltage power supply 116. Prior to applying the high voltageto the inner electrode 112, both the inner electrode 112 and the outerelectrode 114 can be connected to ground voltage to establish a voltagerelationship between the inner electrode 112 and the outer electrode114. A switch can then electrically decouple the outer electrode 114from the high voltage power supply 116. Due to the establishedcapacitive relationship between the inner electrode 112 and the outerelectrode 114, when the high voltage is applied to the inner electrode112, a high voltage will appear on the outer electrode 114.

In one embodiment, the outer electrode(s) 114 can be produced bydepositing a conductive material on the dielectric body 104 such thatthe dielectric body 104 is covered by the conductive material. A mask isthen placed on the conductive material. The mask has a pattern accordingto which the outer electrode(s) 114 will be formed. With the maskcovering the surface of the conductive material, the ionizer 101 isplaced in a liquid etchant such as potassium hydroxide (KOH) or anothersuitable etchant that will selectively etch the conductive material inthose areas not covered by the mask without significantly etching thedielectric body 104. When the ionizer 101 is removed from the liquidetchant and the mask is removed, the outer electrode(s) 114 remains. Theparticular etchant can be selected based on the particular materialsfrom which the dielectric body 104 and the outer electrode(s) 114 aremade.

FIG. 4B is a cross section of an ionizer 401, according to oneembodiment. The ionizer 401 is substantially similar to the ionizer 101of FIG. 4A, except that a sharp outer electrode 414 has a triangularcross section. In particular, the sharp outer electrode 414 includes asharp point on a side of the outer electrode 114 furthest from the innerelectrode 112. The ionizer 401 operates in a substantially similarmanner as the ionizer 101 of FIG. 4A.

While an outer electrode having a triangular cross-section and an outerelectrode having a rectangular cross-section have been disclosed, othershapes are possible for the outer electrodes 114 as will be understoodby those of skill in the art in light of the present disclosure. Forexample, the outer electrodes 114 can have a cross-section correspondingto that of a thin rounded wire. All such other electrode shapes fallwithin the scope of the present disclosure.

FIG. 5 is a cross section of an ionizer 501, according to an alternateembodiment. The ionizer 501 has a substantially rectangularcross-section. In particular, an inner electrode 512 and a dielectricbody 504 of the ionizer 501 have a rectangular cross-section. An outerelectrode 414 is positioned on the on the dielectric body 504. Thoughnot shown in the figures, those of skill in the art will understand, inlight of the present disclosure, that many other shapes andconfigurations can be implemented for an ionizer in accordance withprinciples of the present disclosure. All such other shapes andconfigurations fall within the scope of the present disclosure.

FIG. 6 is a diagram showing a combustion system 600 including an ionizer101 and a counter electrode 628, according to an embodiment. The counterelectrode 628 is proximate to the combustion reaction 110. The ionizer101 includes an inner electrode 112 (see FIGS. 1-3) and a plurality ofouter electrodes 114 isolated from the inner electrode 112 by thedielectric body 104. A high voltage power supply 116 is operativelycoupled to the counter electrode 628 by a voltage output node 622, andto the inner electrode 112 of the ionizer 101 by a voltage output node118.

In the combustion system 600 of FIG. 6, the counter electrode 628 hasthe shape of a torus or a toroid surrounding the combustion reaction 110and positioned a selected distance above the conductive combustionsupport structure 124. In one embodiment, the counter electrode 628lacks the sharp features of the outer electrode 114. Therefore, thestrength of the electric field in the immediate vicinity of the counterelectrode 628 is not as great as the strength of the electric field inthe immediate vicinity of the sharp outer electrode 114. The counterelectrode 628 does not tend to eject charge into or induce ionization ofthe surrounding dielectric medium.

In one embodiment, the counter electrode 628 is configured so that theelectric field adjacent to it is about equal to or less than the averageelectric field magnitude in the region between the outer electrodes 114and the counter electrode 628.

The counter electrode 628 is operatively coupled to the high voltagepower supply 116. In one embodiment, the counter electrode 628 can beheld substantially at ground potential, or can be configured to bedriven to an instantaneous voltage substantially the same as theinstantaneous voltage applied to the outer electrodes 114.Alternatively, the counter electrode 628 can be configured to begalvanically isolated from ground and from other electrical potentials.

FIG. 7 is a diagram of a combustion system 700, according to oneembodiment. The combustion system 700 includes a combustion wall orenclosure 730 defining an inner furnace volume 732. An ionizer 101extends into the furnace volume 732 through an aperture in an upperportion of the wall 730. The conductive combustion support structure 124sustains a combustion reaction 110 within the furnace volume 732. A fuelsource 734 provides fuel to the conductive combustion support structure124. A high voltage power supply 116 is electrically coupled to theconductive combustion support structure 124 into the ionizer 101.

The conductive combustion support structure 124 is a conductive flameholder or fuel nozzle that supports the combustion reaction 110.According to one embodiment, ground voltage is applied to the conductivecombustion support structure 124 by the high voltage power supply 116.Because the combustion reaction 110 is conductive, the ground voltage isimparted to the combustion reaction 110 by the conductive combustionsupport structure 124.

In one embodiment, the ionizer 101 is configured substantially asdescribed in relation to FIG. 1. The ionizer 101 can include an innerelectrode 112 covered in a dielectric body 104. Outer electrodes 114 arepositioned on the outside of the dielectric body 104. The outerelectrodes 114 are electrically insulated from the inner electrode 112by the dielectric body 104. Nevertheless, the outer electrodes 114 arecapacitively coupled to the inner electrode 112. The outer electrodes114 are separated from the combustion reaction 110 by a dielectric gap120 containing a dielectric gas such as air or flue gas.

The high voltage power supply 116 is configured to supply a high voltageto the inner electrode 112 of the ionizer 101. Due to capacitivecoupling between the inner electrode 112 and the outer electrodes 114,when the high voltage power supply 116 supplies the high voltage to theinner electrode 112, a high voltage is also induced on the outerelectrodes 114.

The combustion reaction 110 can be manipulated by applying respectivevoltages to the inner electrode 112 and to the combustion reaction 110.In particular, the combustion reaction 110 can be manipulated to changethe color of the combustion reaction 110, to make the combustionreaction 110 not apparent, to stretch the length of the flame, tocontract length of the flame, to more thoroughly combust the fuel, toreduce pollutants, etc.

Typically, as shown in FIG. 7, the ionizer 101 is separated from thecombustion reaction 110 by dielectric gap 120. However, it is possiblein some circumstances that direct contact will occur between thecombustion reaction 110 and one or more of the outer electrodes 114. Insome circumstances, it is even possible that the ionizer 101 will beintentionally positioned within the combustion reaction 110. In theevent that the ionizer 101 is in direct contact with the combustionreaction 110, a short circuit of the high voltage power supply 116 isprevented because the outer electrodes 114 are electrically insulatedfrom the high voltage power supply 116 by the dielectric body 104covering the inner electrode 112. Thus, in the event of accidental orintentional contact between the ionizer 101 and the combustion reaction110, a short circuit will not occur.

FIG. 8 is a flow diagram of a process 800 for operating a combustionsystem, according to one embodiment. At 802, a combustion reaction isimplemented and sustained in the combustion system. The combustionreaction can include combustion between a fuel and oxygen sourceinjected into the combustion volume.

At 804, a high voltage is applied to an inner electrode of an ionizer.The inner electrode of the ionizer is covered by a dielectric body. Anelectrode is positioned on the outside of the dielectric body. The outerelectrode is electrically insulated from the inner electrode by thedielectric body. Nevertheless, the outer electrode is capacitivelycoupled to the inner electrode by the dielectric body.

At 806, a high voltage is induced on the outer electrode by thecapacitive coupling between the outer electrode and the inner electrode.Thus, when the high voltage is applied to the inner electrode, a highvoltage is induced on the outer electrode by capacitive coupling withthe inner electrode.

At 808, a second voltage is applied to a counter electrode electricallycoupled to the combustion reaction. The counter electrode can be a fuelnozzle from which fuel for the combustion reaction is emitted, aconductive mesh on which a solid fuel rests, a flame holder configuredto hold the combustion reaction, or a conductor otherwise positioned inor near the combustion reaction. Because a flame conducts electricity,the second voltage is imparted to the flame by the counter electrode. At810, a characteristic of the combustion reaction is manipulated bycontrolling the high voltage. The high voltage induces a strong electricfield adjacent to the electrode of the ionizer. The strong electricfield can eject charges from the electrode, can attract charges to theelectrode, can cause ions or charged particles within the flame tobehave in a certain way, etc. In this way, a desired effect can beintroduced in the combustion reaction by applying respective voltages tothe inner electrode and the counter electrode.

In the foregoing description, an ionizer or ion source has beendescribed. Nevertheless, in some embodiments the ionizer or ion sourcemay not, in fact, be a source of ions, but may instead merely manipulatea combustion reaction by influencing via electric field/electricpotential ions or free charges already present in the combustionreaction. Nevertheless, the terms “ionizer” and “ion source” still applyto such other embodiments, even if the function is not to ionize or actas an ion source.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments are contemplated. The various aspects andembodiments disclosed herein are for purposes of illustration and arenot intended to be limiting, with the true scope and spirit beingindicated by the following claims.

What is claimed is:
 1. A method, comprising: applying a first highvoltage signal to an inner electrode of an ionizer positioned adjacentto a combustion reaction, the ionizer including a dielectric bodycovering the inner electrode and one or more outer electrodes disposedon the dielectric body; causing the one or more outer electrodes to forma charged particle in a dielectric gap between the ionizer and thecombustion reaction via capacitive coupling of the outer electrodes withthe inner electrode; and providing the charged particle to thecombustion reaction to influence a characteristic of the combustionreaction.
 2. The method of claim 1, wherein applying the first highvoltage signal includes applying a periodic voltage signal.
 3. Themethod of claim 2, wherein the first high voltage signal has apeak-to-peak voltage greater than 1000V.
 4. The method of claim 2,wherein the first high periodic voltage signal has a peak-to-peakvoltage greater than 40,000V.
 5. The method of claim 1, furthercomprising applying a second voltage signal to a counter electrodeseparate from the ionizer.
 6. The method of claim 5, further comprising:outputting fuel for the combustion reaction from a combustion supportstructure, wherein the combustion support structure includes the counterelectrode.
 7. The method of claim 6, wherein the counter electrode is aconductive ring positioned proximate to the combustion reaction.
 8. Themethod of claim 5, wherein applying the second voltage signal includesapplying a ground voltage.
 9. The method of claim 1, wherein the one ormore outer electrodes are metal.
 10. The method of claim 1, wherein theone or more outer electrodes include a doped semiconductor material. 11.The method of claim 1, wherein the first high periodic voltage signal isan AC voltage signal.
 12. The method of claim 1, wherein the first highperiodic voltage signal is a sawtooth voltage signal.